import javax.swing.tree.TreeNode;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Stack;

/**
 * @author xizizzz
 * @description: TODO
 * @date 2021-9-3上午 08:14
 */
public class qian {
    public static void main(String[] args) {
        System.out.println(2.0 - 1.1);
        String[] str = new String[]{"a1", "a2", "c1", "d", "a3", "c3"};
        Arrays.sort(str);
        for (String s : str) {
            System.out.print(s + " ");
        }
    }


    class TreeNode {

    }
}
